Status and Availability

20 August 2012
Following discussions with the STAC and Board, we do not anticipate offering Michelle as a facility instrument in future Semesters.

27 January 2012
Due to low demand Michelle is not currently scheduled for queue or classical observations in 2012A.

9 March 2011
Michelle is not offered in polarimetry mode, either imaging polarimetry or spectropolarimetry, in 2011B. There is currently a software issue with the control of the waveplate for the polarimetry mode and this will not be fixed for 2011B.

2 December 2008
Due to low demand Michelle is not currently scheduled for queue observations in 2009A.

25 November 2008
The chop-induced elongation seen in Michelle images from 2006 to 2008 has been removed by work on the guiding/chopping interactions in 2008A. Following the change of the secondary mirror in late October 2008 the Michelle images were subject to elongation in the elevation xis direction. This problem was resolved by re-tuning the disturbance rejection of the secondary control system. As of late November 2008 the image quality is much better than it has been for most of the past 2 to 3 years. A discussion of the details of the Michelle PSF is available for anyone who is interested.

1 November 2008
Michelle spectral polarimetry mode will not be commissioned in 2008B or 2009A. This was decided during the observatory planning for 2009, based in part upon input from the Operations Working Group.

1 July 2008
There is a bad channel in Michelle. This appeared in early 2008 after a warm up and cool down of the instrument to improve the thermal contact of the detector with the cold finger. Some attempts were made to fix this problem in the summer of 2008 but these failed and it appears that we have to live with this situation for the long term. This has some implications for both imaging and spectroscopy observations.